[solved] Slow scrolling of Unicode files in Lister (64bit)

[petermad]

On slow pc's with slow operating systems (Win 8 and 10) there is a delay in scrolling Unicode and UTF-8 files (they do not scroll in real-time) with 64bit TC but not with 32bit TC.

See more at: http://ghisler.ch/board/viewtopic.php?p=340091#340091

This also applies to TC 9.52a 64bit

[ghisler(Author)]

No problem here - my PC is from 2010, so not the fastest, but I don't have any scrolling problems. Mybe it's caused by some third party tool, e.g. coming with the mouse?

[petermad]

I am using Microsofts default driver for the mouse - nothing special. And it is only the 64bit version of TC that is affected - I guess if it was a mouse driver problem it would be seen in both TC versions.

I testet with a clean ini file too, so it is not any special setting that causes it.

When I test, I scroll down turning the wheel 3-4 times quickly one after the other, and when I release the wheel, I se scrolling going on for like ½ a second thereafter. If I just scroll slowly one wheel-turn at the time, I don't experience the problem.

[milo1012]

I can actually confirm this: definitely a slower scroll speed in x64 TC than in 32-bit.
Tested on Win7 x64, no special mouse drivers.
It doesn't matter if I enabled "Smooth scroll list boxes" or not.

I guess it's a Uniscribe/Lazarus related issue.

[ghisler(Author)]

I couldn't reproduce this so far. Do you have a sample file to test it?

[petermad]

Do you have a sample file to test it

Just export you entire Windows Registry to a .reg file - that is what I testet with - as mentioned here: http://ghisler.ch/board/viewtopic.php?p=340091#340091

[ghisler(Author)]

I tried with a registry file, 240MB large. However, I cannot see the slightest difference between TC 32-bit and 64-bit. Scolling is immediate in both.

[petermad]

It is not whether the scrolling starts immediately it is whether it stops immediately.

It is when I make severalt continous turns with the whell, then the scrolling can't keep up, and then when I release the wheel, I see scrolling still taking place for maybe ½ a second, before the scrolling stops.

And only in 64bit TC and more pronounced on slow computers with more demanding OS's (windows 8 or 10).

[ghisler(Author)]

Ah, I see - I think I found a solution: Currently when TC gets one mouse wheel message, and the scroll lines per message is 3 (the Windows default), TC sends 3 WM_VSCROLL messages to itself. Combining the 3 into my own custom scroll message which scrolls 3 lines in one step seems to fix the problem. Please test once beta 2 comes out.

[petermad]

Confirmed fixed in TC 9.20b2

[ghisler(Author)]

Nice to hear that! I could only reproduce the problem by giving the mouse wheel a big "kick" with a finger.